Miyazaki Hiroshi, Takitani Kimitaka, Koh Maki, Inoue Akiko, Kishi Kanta, Tamai Hiroshi
Department of Pediatrics, Osaka Medical College.
J Nutr Sci Vitaminol (Tokyo). 2014;60(2):78-85. doi: 10.3177/jnsv.60.78.
Retinol and its derivative, retinoic acid, have pleiotropic functions including vision, immunity, hematopoiesis, reproduction, cell differentiation/growth, and development. Non-alcoholic fatty liver disease (NAFLD) is one of the most common diseases in developed countries and encompasses a broad spectrum of forms, ranging from steatosis to steatohepatitis, which develops further to cirrhosis. Retinol status has an important role in liver homeostasis. The purpose of this study was to evaluate the retinol status and expression of retinol-related proteins, including enzymes and binding proteins, in methionine-choline deficient (MCD) rats as a model of NAFLD. We examined retinol levels in the plasma and liver and gene expression for β-carotene 15,15'-monooxygenase (BCMO), lecithIn: retinol acyltransferase (LRAT), aldehyde dehydrogenase 1A1 (ALDH1A1), ALDH1A2, and cellular retinol binding protein (CRBP)-I in MCD rats. The plasma retinol levels in MCD rats were lower than those in the controls, whereas hepatic retinol levels in MCD rats were higher. BCMO expression in the intestine and liver in MCD rats was lower, whereas that in the testes and the kidneys was higher than in control rats. Expression of LRAT, CRBP-I, ALDH1A1, and ALDH1A2 in the liver of MCD rats was also higher. Altered expression of retinol-related proteins may affect retinol status in NAFLD.
视黄醇及其衍生物视黄酸具有多种功能，包括视觉、免疫、造血、生殖、细胞分化/生长以及发育。非酒精性脂肪性肝病（NAFLD）是发达国家最常见的疾病之一，涵盖了从脂肪变性到脂肪性肝炎等广泛的形式，后者会进一步发展为肝硬化。视黄醇状态在肝脏稳态中起着重要作用。本研究的目的是评估作为NAFLD模型的蛋氨酸-胆碱缺乏（MCD）大鼠的视黄醇状态以及视黄醇相关蛋白（包括酶和结合蛋白）的表达。我们检测了MCD大鼠血浆和肝脏中的视黄醇水平，以及β-胡萝卜素15,15'-单加氧酶（BCMO）、卵磷脂：视黄醇酰基转移酶（LRAT）、醛脱氢酶1A1（ALDH1A1）、ALDH1A2和细胞视黄醇结合蛋白（CRBP）-I的基因表达。MCD大鼠的血浆视黄醇水平低于对照组，而MCD大鼠的肝脏视黄醇水平较高。MCD大鼠肠道和肝脏中的BCMO表达较低，而睾丸和肾脏中的BCMO表达高于对照大鼠。MCD大鼠肝脏中LRAT、CRBP-I、ALDH1A1和ALDH1A2的表达也较高。视黄醇相关蛋白表达的改变可能会影响NAFLD中的视黄醇状态。
